shell: Add support to wayland primary outputs
Refactors XRandr support together with the new Wayland code into a PrimaryOutputWatcher class. For X11 it listens to xcb events. For Wayland it uses the kde_output_management_v2 protocols.
Depends on kwin!1563 (merged)
See #21 (closed)
Edited by Aleix Pol Gonzalez